helene dutrieu



PATENTBD JAN. 12, 1904.

837 I W H. DUTRIEU. CONSTRUCTION OF SWITGHBAGK ROADWAYS.

APPLICATION FILED AUG. 19. 1903.

N0 MODEL. F70, 67 6 jg Z.

M. v 1 E2 UNITED STATES PATENT OFFICE.

HELEN t DUTRIEU, OF PARIS, FRANCE.

CONSTRUCTION OF SWl'l'CHBACK-ROADWAYS.

SPECIFICATION forming part of Letters Patent N 0. 749,607, dated January 12, 1904.

Application filed august 19, 1903. Serial No. 170,042. (No model.)

T0 at whom it may concern:

Be it known that I, HE ENE DUTRIEU, residing in Paris, France, have invented certain new and useful Improvements in Interrupted Tracks for Cycles, of which the following is a specification.

This invention relates to amusement or re creation devices wherein an inclined and interrupted track is employed down which a cyclist rides, the impetus carrying the rider safely beyond the gap or interruption in the track.

In the accompanying drawings, which serve to illustrate an embodiment of the invention, Figure 1 is a side elevation of the track. Fig. 2 is a plane of the same, and Fig. 3 is a perspective view of the same.

The track consists of the parts a, a (1?, a, and a and is upheld by a suitable support, which may be a frame. I), of iron. At its upper end the track has a startingplatform 0. At (Z, between the parts a and u of the track, is a void or interruption, forming a gap across or over which the rider must leap with his cycle, as indicated in Fig. l.

The material and essential features of the invention reside in the peculiar contour of the track. and this will now be described.

The main portion (1- of the track is inclined, extending from the elevated platform down to the point where it is joined by the concave curved portion a with the part a at the margin of the gap 11. This portion a is inclined upward and is a plane tangent to the parabolic curve of the trajectory or path followed by the rider. as indicated in dotted lines in Fig. 1, The portions (6 and a are tangent to the curved portion 1.1-, or substantially so. The portion 11- ot' the track which joins the terminal inclined portion a at the theoretical point 1 where the parabolic trajectory meets the track beyond the gap, is slightly convex and may be mounted on springs or made springy. it is of course calculated that the cycle will in every descent of the track follow the theoretical parabolic path and impinge on the terminaltrack a at y, said track a being, like the portion a, tangent to the said path; but as this cannot always be complied with accurately and the point of impact may vary slightly from several causes the portion a of the track is provided and disposed between the theoretical point of impact 1 and the margin of the gap (1 to receive the cycle and prevent it and the rider from' falling into the gap (Z. To further cushion the shock of the impact in case the cycle alights on the part a of the track, this part may have loose materialsuch' as earth, sand, sawdust, or the likespread over it.

The track may be marked with lines f (seen in Fig. 2) to guide the rider and enable the latter to keep an exact middle course, and as a precaution the part a may be made wider, as seen in Fig. 2, than the other parts of the track in order to allow for some lateral deviation of the cycle in bounding over the gap and alighting on the part of the track beyond.

In case the track is sufiiciently elevated at the platform a and long enough there might be more than one gap or interruption in it; but as this would be a mere repetition of what is shown no further illustration will be necessary.

It is essential to the safe and proper operation of this track that the up\vardl '-inclined plane portion a of the track where the cycle takes the leap shall have a length at least equal to the distance between the centers of the front and rear wheels of the cycle used, as otherwise the latter will not follow the parabolic trajectory contemplated and be plunged into the open gap (Z.

Having thus described my invention, I claim An elevated cycletrack for the purpose specified, comprising a downwardLv-inclined portion a, an upwardly-inclined portion a at the margin of a gap in the track and joined to the portion a by a curved portion 0-, said portion (1- being tangent to the parabolic curve In witness whereof I have hereunto signed of the path traveled by the cycle in leaping my name, this 4th day of August, 1903, 1n the the gap, and having a length as great as the presence of two subscrxbmg witnesses.

distance between the centers of the oyele- HELENE DUTRIEU, 5 wheels, and a terminal downwardly-inclined Wit portion of the track beyond said gap and also JULES ARMENGAUmJeune,

tangent to the said parabolic path. AUGUSTUS E INGRAM 

